Publications
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Craters of habit: Patterns of deformation in the western Galápagos Craters of habit: Patterns of deformation in the western Galápagos
The western Galápagos islands of Fernandina and Isabela comprise six active volcanoes that have deformed since first observed by satellite radar in the early 1990s. We analyse new (2015–2022) displacement time series at Alcedo, Cerro Azul, Darwin, Fernandina, Sierra Negra, and Wolf volcanoes in the context of deformation and unrest since 1992. Previous discussions of volcano deformation...
Authors
Eoin Reddin, Susanna K. Ebmeier, Marco Bagnardi, Andrew F. Bell, Pedro Espin Bedon
Following the tug of the audience from complex to simplified hazards maps at Cascade Range volcanoes Following the tug of the audience from complex to simplified hazards maps at Cascade Range volcanoes
Volcano-hazard maps are broadly recognized as important tools for forecasting and managing volcanic crises and for disseminating spatial information to authorities and people at risk. As scientists, we might presume that hazards maps can be developed at the time and with the methods of our discretion, yet the co-production of maps with stakeholder groups, who have programmatic needs of...
Authors
Carolyn L. Driedger, David W. Ramsey, William E. Scott, Lisa M. Faust, Joseph A. Bard, Patti Wold
Using ground crack and very low frequency measurements to map the location of the June 2007 Father’s Day dike, Kīlauea Volcano Using ground crack and very low frequency measurements to map the location of the June 2007 Father’s Day dike, Kīlauea Volcano
An intrusion into Kīlauea’s upper East Rift Zone during June 17–19, 2007, during the 1983–2018 Pu‘u‘ō‘ō eruption, led to widespread ground cracking and a small (approximately 1,525 cubic meters) eruption on the northeast flank of Kānenuiohamo, a cone about 6 kilometers upslope from Pu‘u‘ō‘ō. Transmitted and induced very low frequency (VLF) magnetic fields were measured with a handheld...
Authors
Tim R. Orr, James P. Kauahikaua, Christina Heliker
Tracking magma pathways and surface faulting in the Southwest Rift Zone and the Koaʻe fault system (Kīlauea volcano, Hawai ‘i) using photogrammetry and structural observations Tracking magma pathways and surface faulting in the Southwest Rift Zone and the Koaʻe fault system (Kīlauea volcano, Hawai ‘i) using photogrammetry and structural observations
Volcanic islands are often subject to flank instability, resulting from a combination of magmatic intrusions along rift zones and gravitational spreading causing extensional faulting at the surface. Here, we study the Koaʻe fault system (KFS), located south of the summit caldera of Kīlauea volcano in Hawaiʻi, one of the most active volcanoes on Earth, prone to active faulting, episodic...
Authors
Stefano Mannini, Joel Ruch, Richard W. Hazlett, Drew T. Downs, Carolyn Parcheta, Steven P. Lundblad, James Anderson, Ryan L. Perroy, Nicolas Oestreicher
2021 Volcanic activity in Alaska and the Commonwealth of the Northern Mariana Islands—Summary of events and response of the Alaska Volcano Observatory 2021 Volcanic activity in Alaska and the Commonwealth of the Northern Mariana Islands—Summary of events and response of the Alaska Volcano Observatory
In 2021, the Alaska Volcano Observatory responded to eruptions, volcanic unrest or suspected unrest, increased seismicity, and other significant activity at 15 volcanic centers in Alaska and the Commonwealth of the Northern Mariana Islands. Eruptive activity in Alaska consisted of repeated small, ash-producing, phreatomagmatic explosions from Mount Young on Semisopochnoi Island; an...
Authors
Tim R. Orr, Hannah R. Dietterich, David Fee, Tarsilo Girona, Ronni Grapenthin, Matthew M. Haney, Matthew W. Loewen, John J. Lyons, John A. Power, Hans F. Schwaiger, David J. Schneider, Darren Tan, Liam Toney, Valerie K. Wasser, Christopher F. Waythomas
2020 Volcanic activity in Alaska—Summary of events and response of the Alaska Volcano Observatory 2020 Volcanic activity in Alaska—Summary of events and response of the Alaska Volcano Observatory
The Alaska Volcano Observatory responded to eruptions, volcanic unrest or suspected unrest, increased seismicity, and other significant activity at nine volcanic centers in Alaska in 2020. The most notable volcanic activity in 2020 was an eruption of Shishaldin Volcano, which produced lava flows, lahars, and ash. Mount Cleveland had one small ash-producing eruption in June but was quiet...
Authors
Tim R. Orr, Cheryl Cameron, Hannah R. Dietterich, Matthew W. Loewen, Taryn Lopez, John J. Lyons, Jenny Nakai, John A. Power, Cheryl Searcy, Gabrielle Tepp, Christopher F. Waythomas
Versatile modeling of deformation (VMOD) inversion framework: Application to 20 years of observations at Westdahl Volcano and Fisher Caldera, Alaska, US Versatile modeling of deformation (VMOD) inversion framework: Application to 20 years of observations at Westdahl Volcano and Fisher Caldera, Alaska, US
We developed an open source, extensible Python-based framework, that we call the Versatile Modeling of Deformation (VMOD), for forward and inverse modeling of crustal deformation sources. VMOD abstracts from specific source model implementations, data types and inversion methods. We implement the most common geodetic source models which can be combined to model and analyze multi-source...
Authors
Mario Angarita, Ronni Grapenthin, Scott Henderson, Michael S Christoffersen, Kyle R. Anderson
Mesoproterozoic to Paleozoic tectonics, Pleistocene landforms, and Holocene seismicity in the Blue Ridge: Results from integrated studies of the 9 August 2020, Mw 5.1 earthquake area near Sparta, North Carolina, USA Mesoproterozoic to Paleozoic tectonics, Pleistocene landforms, and Holocene seismicity in the Blue Ridge: Results from integrated studies of the 9 August 2020, Mw 5.1 earthquake area near Sparta, North Carolina, USA
This field trip examines the results of integrated geologic studies of the 9 August 2020, Mw 5.1 earthquake near Sparta, North Carolina, USA. The earthquake generated ~4 km of coseismic surface rupture of the Little River fault and uplifted a surface area of ~11 km 2. The Little River fault is a thrust fault oriented 110–130°/45–70°SW, and mapped fault segments are en echelon with scarp...
Authors
Arthur J. Merschat, Mark W. Carter, Ashley S. Lynn, Kevin G. Stewart, Paula Figueiredo, William Elijah Odom, Ryan J. McAleer, Jorge A. Vazquez, Nicholas Edwin Powell, Christopher S. Holm-Denoma
Lahars: Origins, behavior and hazards Lahars: Origins, behavior and hazards
Volcanic debris flows that originate at potentially active volcanoes are called lahars. Lahars are like debris flows in non-volcanic terrain but can most notably differ in origin and size. Primary lahars occur during eruptions and may have novel origins such as turbulent mixing of hot rock moving across ice- and snow-clad volcanoes and eruptions through crater lakes. Lahars range in...
Authors
James W. Vallance
Numerical modeling of debris flows: A conceptual assessment Numerical modeling of debris flows: A conceptual assessment
Real-world hazard evaluation poses many challenges for the development and application of numerical models of debris flows. In this chapter we provide a conceptual overview of physically based, depth-averaged models designed to simulate debris-flow motion across three-dimensional terrain. When judiciously formulated and applied, these models can provide useful information about...
Authors
Richard M. Iverson, David L. George
Pre-existing ground cracks as lava flow pathways at Kīlauea in 2014 Pre-existing ground cracks as lava flow pathways at Kīlauea in 2014
In 2014, the Pāhoa lava flow at Kīlauea, on the Island of Hawaiʻi (USA), entered a string of pre-existing meter-width ground cracks in the volcano’s East Rift Zone. The ground cracks transported lava below the surface in a direction discordant to the slope of the landscape. The cracks, which were 100s of meters long and 10s to 100s of meters deep, also widened by up to several meters as...
Authors
Tim R. Orr, Edward W. Llewellin, Kyle R. Anderson, Matthew R. Patrick
Arsenic and other geogenic contaminants in global groundwater Arsenic and other geogenic contaminants in global groundwater
Geogenic groundwater contaminants (GGCs) affect drinking-water availability and safety, with up to 60% of groundwater sources in some regions contaminated by more than recommended concentrations. As a result, an estimated 300–500 million people are at risk of severe health impacts and premature mortality. In this Review, we discuss the sources, occurrences and cycling of arsenic...
Authors
Abhijit Mukherjee, Poulomee Coomar, Soumyajit Sarkar, Karen H. Johannesson, Alan Fryar, Madeline Schreiber, Kazi M. Ahmed, Mohd. A. Alam, Prosun Bhattacharya, Jochen Bundschuh, William Burgess, Madhumita Chakraborty, Rachel Coyte, Abida Farooqi, Huaming Guo, Julian Ijumulana, Gh Jeelani, Debapriya Mondal, D. Kirk Nordstrom, Joel Podgorski, David Polya, Bridget R. Scanlon, Mohd. Shamsudduha, Joseline Tapia, Avner Vengosh